Allen-Bradley 505ADD Voltage Reversing Controller

The Allen-Bradley 505ADD is a Bulletin 505 full-voltage reversing controller designed for across-the-line starting and reversing of three-phase AC motors in industrial applications. It incorporates mechanically and electrically interlocked contactors with overload relays to provide safe forward and reverse motor operation, and is commonly used to drive conveyors, pumps, hoists, machine tools, and other manufacturing equipment. This panel-mount, open-style controller operates at 50/60 Hz and reverses motor direction by reversing the phase sequence on three-phase motors, with common replacements including the Allen-Bradley 505-BOD, 505-AOD, and 505-DOD.